@uppy/companion/lib/server/controllers/oauth-redirect.js

OAuth helper and remote fetcher for Uppy's (https://uppy.io) extensible file upload widget with support for drag&drop, resumable uploads, previews, restrictions, file processing/encoding, remote providers like Dropbox and Google Drive, S3 and more :dog:

import qs from 'node:querystring';
import { URL } from 'node:url';
import * as oAuthState from '../helpers/oauth-state.js';
import { hasMatch } from '../helpers/utils.js';
/**
 *
 * @param {object} req
 * @param {object} res
 */
export default function oauthRedirect(req, res) {
    const params = qs.stringify(req.query);
    const { oauthProvider } = req.companion.providerClass;
    if (!req.companion.options.server.oauthDomain) {
        res.redirect(req.companion.buildURL(`/connect/${oauthProvider}/callback?${params}`, true));
        return;
    }
    const { state } = oAuthState.getGrantDynamicFromRequest(req);
    if (!state) {
        res.status(400).send('Cannot find state in session');
        return;
    }
    const handler = oAuthState.getFromState(state, 'companionInstance', req.companion.options.secret);
    const handlerHostName = new URL(handler).host;
    if (hasMatch(handlerHostName, req.companion.options.server.validHosts)) {
        const url = `${handler}/connect/${oauthProvider}/callback?${params}`;
        res.redirect(url);
        return;
    }
    res.status(400).send('Invalid Host in state');
}